Engineering Electromagnetics 1 0909.301.01 Fall 2004

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Engineering Electromagnetics 10909.301.01 Fall
2004
Lecture 6bOctober 13, 2004

• Shreekanth Mandayam
• ECE Department
• Rowan University
• http//engineering.rowan.edu/shreek/fall04/eemag1
  /

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Plan

• Recall Lorentz Force Law
• Motion of a charge in an electrostatic field
• Cathode Ray Oscilloscope
• Ion Thruster
• Magnetostatics
• Direct Currents
• A Leaky Capacitor
• Analogy b/w direct currents and electrostatic
  field
• Matlab PDE Toolbox
• Conductive Media DC mode
• Fields for symmetric current distributions
• Line current
• Coax cable
• Solenoid
• Magnetic Force

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EEMAG-1 Topics Today
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Lorentz Force Law
Force N
Magnetic Flux Density T
Velocity m s-1
Electric Field V m-1
Charge C
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Motion of a Charge in a Uniform Electrostatic
Field
Let
DEMOmotionestat
At time t
At time zero
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Cathode Ray Oscilloscope
Vx
x
anode
cathode
z
screen
Vy
y
deflection plates
VA
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Ion Thruster
Xenon propellant
ions
Xe
Xe
e-
electrons
65,000 mph
Text pp. 350-352
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Direct (Steady) Currents
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Governing Equations
Direct current problems and E-static problems are
analogous!
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A Leaky Capacitor
x
- - - - - - - - - - - - - - - - - - - - -
Permitivity, e Conductivity, s
d
I

z
Vs
I
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Analogy
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Matlab PDE Toolbox

• Conductive Media DC Mode

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Governing Equations
Recall Field due to a line current
dl
Is
f
ds
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Coaxial Cable
Iz
Iz
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Solenoid
y
n turns
x
a
c
z
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Matlab PDE Toolbox

• Magnetostatics Mode

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Summary